微信小程序下拉加载和上拉刷新两种实现方法详解

onPullDownRefresh(){
　　console.log('--------下拉刷新-------')
　　wx.showNavigationBarLoading() //在标题栏中显示加载
　　wx.request({
     url: 'https://URL',
     data: {},
     method: 'GET',
     // OPTIONS, GET, HEAD, POST, PUT, DELETE, TRACE, CONNECT
     // header: {}, // 设置请求的 header
     success: function(res){
      // success
     },
     fail: function() {
      // fail
     },
     complete: function() {
      // complete
      wx.hideNavigationBarLoading() //完成停止加载
      wx.stopPullDownRefresh() //停止下拉刷新
   }
})  

<!--index.wxml-->
 <view class="container" >
  <!--垂直滚动，这里必须设置高度-->
   <scroll-view scroll-top="{{scrollTop}}" scroll-y="true" 
     class="list" bindscrolltolower="bindDownLoad" bindscrolltoupper="topLoad" bindscroll="scroll">
     <view class="item" wx:for="{{list}}">
       <image class="img" src="{{item.pic_url}}"></image>
       <view class="text">
         <text class="title">{{item.name}}</text>
         <text class="description">{{item.short_description}}</text>
       </view>
     </view>
   </scroll-view>
   <view class="body-view">
     <loading hidden="{{hidden}}" bindchange="loadingChange">
       加载中...
     </loading>
   </view>
 </view>

var url = "http://www.imooc.com/course/ajaxlist";
var page =0;
var page_size = 5;
var sort = "last";
var is_easy = 0;
var lange_id = 0;
var pos_id = 0;
var unlearn = 0;
 // 请求数据<br> var loadMore = function(that){
  that.setData({
    hidden:false
  });
  wx.request({
    url:url,<br>    data:{
      page : page,
      page_size : page_size,
      sort : sort,
      is_easy : is_easy,
      lange_id : lange_id,
      pos_id : pos_id,
      unlearn : unlearn
    },
    success:function(res){
      //console.info(that.data.list);
      var list = that.data.list;
      for(var i = 0; i < res.data.list.length; i++){
        list.push(res.data.list[i]);
      }
      that.setData({
        list : list
      });
      page ++;
      that.setData({
        hidden:true
      });
    }
  });
}
Page({
 data:{
  hidden:true,
  list:[],
  scrollTop : 0,
  scrollHeight:0
 },
 onLoad:function(){
  //  这里要注意，微信的scroll-view必须要设置高度才能监听滚动事件，所以，需要在页面的onLoad事件中给scroll-view的高度赋值
   var that = this;
   wx.getSystemInfo({
     success:function(res){
       that.setData({
         scrollHeight:res.windowHeight
       });
     }
   });
    loadMore(that);
 },
 //页面滑动到底部
 bindDownLoad:function(){ 
   var that = this;
   loadMore(that);
   console.log("lower");
 },
 scroll:function(event){
  //该方法绑定了页面滚动时的事件，我这里记录了当前的position.y的值,为了请求数据之后把页面定位到这里来。
   this.setData({
     scrollTop : event.detail.scrollTop
   });
 },
 topLoad:function(event){
  //  该方法绑定了页面滑动到顶部的事件，然后做上拉刷新
   page = 0;
   this.setData({
     list : [],
     scrollTop : 0
   });
   loadMore(this);
   console.log("lower");
 }<br> })

/**index.wxss**/
 
 .userinfo {
  display: flex;
  flex-direction: column;
  align-items: center;
 }
 
 .userinfo-avatar {
  width: 128rpx;
  height: 128rpx;
  margin: 20rpx;
  border-radius: 50%;
 }
 
 .userinfo-nickname {
  color: #aaa;
}
 
 .usermotto {
  margin-top: 200px;
 }
 
 /**/
 
 scroll-view {
  width: 100%;
 }
 
 .item {
  width: 90%;
  height: 300rpx;
  margin: 20rpx auto;
  background: brown;
  overflow: hidden;
 }
 
 .item .img {
  width: 430rpx;
  margin-right: 20rpx;
  float: left;
 }
 
 .title {
  font-size: 30rpx;
  display: block;
  margin: 30rpx auto;
 }
 
 .description {
 font-size: 26rpx;
  line-height: 15rpx;
}